Common wall

[VERMA071]

Hello Everyone,

Detail of common wall between two townhomes (Two family, 3 story) vs Row townhomes.
What is the difference?
Thx,

 

[Joe.B]

Shot in the dark here, I'd guess that the terminology has a lot to do with when and where they were built. I think "Townhomes" is a more modern concept and utilizes stick framing. Again, guessing here, most "Row Houses" utilize masonry walls? Also, I think you may find may row houses are (or were converted to) multi-unit instead of one home from foundation to roof.

 

[VERMA071]

Shot in the dark here, I'd guess that the terminology has a lot to do with when and where they were built. I think "Townhomes" is a more modern concept and utilizes stick framing. Again, guessing here, most "Row Houses" utilize masonry walls? Also, I think you may find may row houses are (or were converted to) multi-unit instead of one home from foundation to roof.

Joe,
i am talking about stick framing. I am working on a two family home in New Jersey. This is a new two family home having a rated wall to separate them. Townhomes have a 2hr rated common wall but with sprinklers, we can have 1 hour rated. My understanding is that the home will have 1 hour rated wall. Am i right? Current code is NJ IRC 2021.
Any UL design for the common wall that I can use. Please see attached plan.
Thx,

 

[Yankee Chronicler]

Hello Everyone,

Detail of common wall between two townhomes (Two family, 3 story) vs Row townhomes.
What is the difference?
Thx,

See the definitions in the IRC as adopted by New Jersey:

[RB] Dwelling: Any building that contains one or two dwelling units used, intended, or designed to be built, used, rented, leased, let or hired out to be occupied, or that are occupied for living purposes.

[RB] Dwelling Unit: A single unit providing complete independent living facilities for one or more persons, including permanent provisions for living, sleeping, eating, cooking and sanitation. For the definition applicable in Chapter 11, see Section N1101.6.

Two-Family Dwelling: A building containing two dwelling units with not more than six lodgers or boarders per dwelling unit.

[RB] Townhouse: A building that contains three or more attached townhouse units.

[RB] Townhouse Unit: A single-family dwelling unit in a townhouse that extends from foundation to roof and that has a yard or public way on not less than two sides.

A two-family dwelling does not contain townhomes (your word) or townhouse units (code word). A two-family dwelling contains two dwelling units. All townhouse units are dwelling units, but not all dwelling units are townhouse units.

Just to be clear: What you are asking is what you need as the dwelling unit separation between the two dwelling units in a two-family dwelling -- is that correct?

 

[Yankee Chronicler]

Follow-up: New Jersey's IRC has diffeeent requirements for the unit separations in townhouse buildings than they do for dwelling unit separations in two-family dwellings. I think you are muddying the issue by referring to/thinking of the two units in this building as "townhomes," which is a term that doesn't appear in the code at all. Separations between townhouse units are addressed in section R302.2, and section R302.2.6 requires each townhouse unit to be structurally independent.

Separations between the two dwelling units in a two-family dwelling are addressed in section R302.3:

For two-family dwellings, there is no requirement that each unit be structurally independent, which means you don't need to use a double stud wall with shaftwall liner as the common wall as you would in a townhouse building.